Density 21.5

Density 21.5 is a specific type of glass used primarily in optical, scientific, and artistic applications. Its name reflects its composition and history: a technical standard established in 1924 that specifies a highly transparent, colorless, and high-quality glass with a density of approximately 2.15 grams per cubic centimeter. This glass is known for its excellent clarity, stability, and optical properties, making it ideal for precision lenses, microscopes, and decorative objects. Its name signifies its exact characteristics, ensuring consistency and reliability in professional uses.